4.1 Link format

Org will recognize plain URL-like links and activate them as
clickable links. The general link format, however, looks like this:

[[link][description]] or alternatively [[link]]

Once a link in the buffer is complete (all brackets present), Org
will change the display so that ‘description’ is displayed instead
of ‘[[link][description]]’ and ‘link’ is displayed instead of
‘[[link]]’. Links will be highlighted in the face org-link,
which by default is an underlined face. You can directly edit the
visible part of a link. Note that this can be either the ‘link’
part (if there is no description) or the ‘description’ part. To
edit also the invisible ‘link’ part, use C-c C-l with the
cursor on the link.

If you place the cursor at the beginning or just behind the end of the
displayed text and press <BACKSPACE>, you will remove the
(invisible) bracket at that location. This makes the link incomplete
and the internals are again displayed as plain text. Inserting the
missing bracket hides the link internals again. To show the
internal structure of all links, use the menu entry
Org->Hyperlinks->Literal links.